
These Two Galaxy Clusters Are About to Smash Into Each Other—Again
Roughly 2.8 billion light-years from Earth, two galaxy clusters are engaged in a cosmic tussle. These enormous structures last collided about a billion years ago, but now, it appears they're going back for round two.
The galaxy clusters involved in this scuffle are part of a larger system—a 'combined' galaxy cluster—called PSZ2 G181. In a study published in The Astrophysical Journal in April, researchers analyzed new observations of PSZ2 G181 that suggest its constituent clusters are poised to smash into each other for a second time.
Major collisions between galaxy clusters are generally considered rare, according to the European Space Agency (ESA), but repeated collisions are decidedly more unusual. What's more, PSZ2 G181's total mass is uncharacteristically low compared to other combined galaxy clusters that have resulted from collisions, adding another layer of peculiarity to the findings.
Astronomers know the individual galaxy clusters that make up PSZ2 G181 crashed into each other once before thanks to previous radio observations, according to a NASA statement.
That work revealed parentheses-shaped regions of diffuse radio emissions on the outskirts of the system. These structures most likely formed as a result of the initial collision a billion years ago.
This new study, led by Andra Stroe, a postdoctoral fellow at the Harvard & Smithsonian Center for Astrophysics, further validates the idea that a previous collision occurred. The researchers analyzed new observations of PSZ2 G181 from two X-ray observatories—NASA's Chandra and the European Space Agency's XMM-Newton. Their study identified a bridge of cool gas connecting the two clusters, which probably resulted from gas stripping during the first collision, according to their report.
Over the last billion years, the two clusters have drifted apart and now sit roughly 11 million light-years away from each other. This is the largest separation between these kinds of structures that astronomers have ever seen, according to NASA's statement.
But Stroe and her colleagues found evidence to suggest these galaxy clusters are now on a collision course again. The team uncovered three more shock fronts aligned with the previous axis of collision—a potential early sign of a second, oncoming crash.
The discovery of this rare event provides new insight into the dynamics of merging galaxy clusters—particularly those involving low-mass systems, which are underexplored. As the researchers note, finding radio emissions from low-mass clusters like PSZ2 G181 is challenging, but 'with the advent of new-generation radio telescopes and surveys, we may be uncovering the 'tip of the iceberg,' they state in their report.
Hashtags

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
2 hours ago
- Yahoo
Scientists Say There's Over a Trillion Dollars of Platinum Waiting to Be Extracted From the Moon's Craters
Researchers say there could be over $1 trillion worth of platinum lurking under the surface of the Moon — a major lunar bounty waiting to be mined. As detailed in a paper published in the journal Planetary and Space Science, independent researcher Jayanth Chennamangalam and his team determined that out of around 1.3 million craters lining the Moon's surface with diameters greater than 0.6 miles across, almost 6,500 were created by asteroids that contain commercial quantities of platinum, among other valuable ores like palladium or iridium. To the researchers, the draw isn't just the promise of immense wealth; the proceeds of mining these ores could be used to explore space. "Today, astronomy is done to satiate our curiosity," Chennamangalam told New Scientist, a surprisingly cynical statement that's bound to raise eyebrows among researchers. "It has very few practical applications and is mostly paid for by taxpayer money, meaning that research funding is at the mercy of governmental policy." "If we can monetise space resources — be it on the Moon or on asteroids — private enterprises will invest in the exploration of the solar system," he added. Chennamangalam, who holds a PhD in astrophysics and was a postdoc at the University of Oxford, found that there could be a "lot more craters on the moon with ore-bearing asteroidal remnants than there are accessible ore-bearing asteroids." Mining these craters would be significantly simpler than traveling to distant asteroids, which most of the time don't have enough gravity for mining operations. But whether plundering the Moon for profit would even be legal remains a far murkier question. As New Scientist points out, the Outer Space Treaty, which was signed in 1967, sets strict rules for space resource mining, stopping any nation from claiming or occupying the "Moon and other celestial bodies." However, experts say those rules could still allow for governments to find loopholes and still claim licensing rights to extract resources. In an effort to ratify international rules, the US established the Artemis Accords, a non-binding framework. However, neither China nor Russia has signed it, leaving its authority murky. In short, the race to the surface of the Moon is on — a tight competition that could be decided between the US and China by the end of this decade, especially if a fortune in precious metals is at play. More on the Moon: Elon Boasts of Huge Starship Improvements Immediately Before It Blows Up Spectacularly
Yahoo
2 hours ago
- Yahoo
Northern Lights Seen Glowing Over Earth in Breathtaking Video Shared by NASA Astronaut: Watch
A NASA astronaut shared a stunning video of the northern lights from space Col. Anne McClain took the footage from the International Space Station The lights, also known as the aurora borealis, were caused by a small geomagnetic stormA NASA astronaut shared a rare and stunning video of the northern lights from space. The footage was shared by Col. Anne McClain, who is onboard the SpaceX Dragon spacecraft docked at the International Space Station (ISS). She specifically shared her view of the lights — also called the aurora borealis — from the Cupola, which is the dome-shaped panoramic control tower on the station. 'Auroras from space always draw crewmembers to the Cupola. I love how this one illuminated our Dragon, and I also love the dance of satellites on the left in the latter part of the video,' she captioned the video on X. 'It's interesting how the aurora creeps along the top of the atmosphere as it comes up over the horizon,' she added. 'I have added traveling to see auroras from Earth to my bucket list!' In an X post also shared on June 2, NASA astronaut Nichole 'Vapor' Ayers, who is also on the ISS, explained that the 'sun has been pretty active over the last week, which means some phenomenal auroras!' A forecast from the National Oceanic and Atmospheric Administration (NOAA) stated that geomagnetic storms created an increased chance of seeing the Northern Lights this past week, per the BBC. According to NOAA, a geomagnetic storm is a disturbance of Earth's magnetosphere — a.k.a. the region around the planet dominated by a magnetic field. The disturbances occur when there is an exchange of energy between solar wind and the 'space environment' surrounding Earth. NOAA states that while these storms can create beautiful auroras, large storms can disrupt navigation systems and even cause harmful currents to Earth's power grids — though the most recent storms have been too mild to do so. And as to why the northern lights emit different colors? Never miss a story — sign up for to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories. It's dependent on the interaction of space particles with specific gases in the atmosphere, per NASA. Space particles that interact with oxygen produce green or red light, while nitrogen gas produces blue or pink hues. The light emitted from the gases can also appear to blend and mix, creating purple and white light. Read the original article on People


USA Today
3 hours ago
- USA Today
These are the best times to view June's strawberry moon
These are the best times to view June's strawberry moon A strawberry moon will dazzle skywatchers June 11. This year's strawberry moon will be a micromoon – which means it will appear dimmer and smaller than usual – and will be at its fullest at 3:44 a.m. ET, according to NASA. But because it's so early in the day, the best time to view the moon will be June 10, when it rises at sunset, according to LiveScience. The moon is expected to be a shade of gold rather than a vibrant shade of red like a strawberry, if weather conditions allow. The spectacle marks the last full moon before the summer solstice, when we officially say goodbye to spring. The moon also will appear about 14% smaller and 30% dimmer because it will be near its farthest point from Earth. Why is it called the strawberry moon? According to the Almanac, the name "strawberry moon" comes from the Native American Algonquian tribes, who lived in the northwestern United States. The Ojibwe, Dakota and Lakota tribes also used the name, which marked the wild strawberries in June. Where to view the strawberry moon June's full moon will be among the lowest in the sky of the year because of its low arc. Its moonlight will reflect the Earth's atmosphere, giving it a yellow or orange tint. On June 11, the full moon rises in the east shortly before sunset, which makes it the best time to see it from North America. Check the moonrise and moonset times in your location, then pick a site where you can see the eastern horizon at a low angle. You can use an online tool from The Old Farmer's Almanac to determine the local moonrise and moonset times. Try searching your city or ZIP code here. June's phases of the moon The moon takes about 29½ days to revolve around Earth, which is called a lunar cycle, according to the Lunar and Planetary Institute. As the moon moves through its various stages, it experiences several phases of partial light. These range from a banana-shaped crescent moon, a D-shaped quarter moon and a nearly full gibbous moon. When are the full moons in 2025? There are seven full moons remaining this year; three will be supermoons. SOURCE NASA, The Old Farmer's Almanac, University of Arizona, Lunar & Planetary Laboratory, USA TODAY Network and USA TODAY research